Document feeding device

ABSTRACT

APPARATUS FOR SORTING DOCUMENTS BY MEANS OF VACUUM CHAMBER APPLICATION THROUGH A PERFORATED CONVEYOR BELT. THE APPARATUS IS CHARACTERIZED BY PROVIDING MEANS FOR PREVENTING TWO OR MORE DOCUMENTS FROM BEING SIMULTANEOUSLY SEPARATED FROM THE STACK CONTAINED IN A MAGAZINE. PRSSURIZED AIR IS DIRECTED AGAINST THE LEADING TRANSVERSE EDGE OF THE DOCUMENTS IN AN OBLIQUE DIRECTION RELATIVE TO THE DOCUMENT PLANE. A VACUUM IS CREATED SUBSTANTIALLY OPPOSITE THE VACUUM CHAMBER FOR APPLYING TO THE OPPOSITE SIDE OF THE DOCUMENTS SUCTION DIRECTED PERPENDICULAR TO THE PLANE THEREOF. THE DOCUMENTS ARE SUBJECTED ALSO TO A SECOND AIR PRESSURE IN THE SAME DIRECTION AS THE ABOVEMENTIONED PERPENDICULAR VACUUM.

sept. 20, 1971 Filed. Aug. 15, 1969 5 Sheets-Sheet 1 lnvenlors AYNOND G.R. O. DEAC'ERE k//LLY A. F. MNS

BWMZ w gen:

sapt. 20, '1971 3,6os,3os

R.l G. REMIGlUS-DOMINICUS DEBACKERE ETL DOCUMENT FEEDING DEVICE I FiledAug.- 15, 1989 '8 shets-sheet s RYNOND C. R. D. MJACKER WILLY A. F- MENSUnited States Patent O 3,606,305 DOCUMENT FEEDING DEVICE Raymond GilbertRemigius-Dominicus Debackere, Edegem, and Willy Alfons Franciscus Mens,Wommelgem, Belgium, assignors to International Standard ElectricCorporation, New York, N .Y.

Filed Aug. 15, 1969, Ser. No. 850,406 Claims Priority, applicationNetherlands, Aug. 23, 1968, 6812027 Int. Cl. B65h 3/12 U.S. Cl. 271-2611 Claims ABSTRACT OF THE DISCLOSURE Apparatus for sorting documents bymeans of vacuum Chamber application through a perforated conveyor belt.The apparatus is Characterized by providing =means for preventing two ormore documents from being simlultaneously separated from the stackcontained in a magazine. Pressurized air is directed against the leadingtransverse edge of the documents in an oblique direction relative to thedocument plane. A vacuum is created substantially opposite the vacuumChamber for applying to the opposite side of the documents suctiondirected perpendicular to the plane thereof. The documents are subjectedalso to a second air pressure in the same direction as theabovementioned perpendicular vacuum.

BACKGROUND OF THE INVENTION The present invention relates to a documentfeeding device including a 'magazine for documents, a feed belt passingadjacent to the magazine and along one side of a feed path for thedocuments and having at least one opening therein, a vacuum Chamberpositioned adjacent to the feed belt along one side of the path andhaving at least one opening therein, and means for exhaustng air in thevacuum Chamber wherein the vacuum -chamber is operable in Cooperationwith the opening in the feed belt to cause one document at a time to bewithdrawn from the magazine and to be moved along the feed path.

Such a document feeding device is already known from U.S. Pat. No.3,067,998. This known device includes a reverse belt passing along theother side of the feed path and opposite direction to that of the feedbelt, said reverse belt being mounted along a second hollow vacuumcha'mber having at least one opening therein. This second vacuum Chamberis operable in Cooperation with openings in the reverse belt, the aim ofwhich is to retain the documents in the magazine except those documentswithdrawn one at a time therefrom. The reverse belt however alsofunctions as a return belt if more than one document is withdrawn fromthe magazine since any document not directly influenced by the vacuumapplied through openings in the feed belt will contact the return beltand be returned to the magazine by the efiect of the vacuum applied tothis document through the second vacuum Chamber associated with thereturn belt.

It has now been found that this reverse belt only operates correctlywhen the documents are relatively stift. Indeed, when this is not so thedocuments to be returned to the magazine are buckled by the return beltand damaged.

SUMMARY OF THE INVENTION It is therefore an object of the presentinvention to provide a document feeding device which does away with thereverse belt and which is adapted to handle documents having any degreeof stiffness at high speeds, e.g., 20 to 40 documents per second.

The present document feeding device is particularly characterized inthat it further includes means supplying Patentecl Sept. 20, 1971 ICC astream of air and directing at least a portion thereof between the feedbelt and the magazine in such a manner that said portion has a directionsubstantially opposite to the direction of displacement of the feed beltto cause the documents to be retained in the magazine except thosedocuments withdrawn one at a time therefrorn.

An other characteristic of the present document feeding device is thatthe -means supplying and directing the stream of air are constituted bya pressure Chamber positioned along the other side of the feed pathhaving at least one opening therein and being coupled to a source ofpressurized air, wherein the opening communicates with a channel suchthat the stream of air issuing therefrom is oblique with respect to thedirection of displacement.

By the action of the portion of said stream of air, the leading edges ofthe documents subjected to this portion of air are much as possibleprevented from sticking to one another, so that in principle only thefront document in the magazine may be subjected to the action of thefeed belt and withdrawn from this magazine. If together with the frontdocument other documents are howe'ver withdrawn from the magazine, theabove portion of air considerably brakes or even stops these documents.

Still another characteristic of the present document feeding device isthat it further includes a second vacuum Chamber positioned along theother side of the feed path, the second vacuum Chamber having at leastone opening therein and being coupled to exhausting means.

Yet another characteristic of the present document feeding device isthat it further includes a second pressure Chamber positioned along theone side of the path in front of the second vacuum Chamber, the secondpressure Chamber having at least one opening therein and being coupledto a source of pressurized air.

By the combined action of the second vacuum Chamber and the secondpressure Chamber, the other documents withdrawn from the magazinetogether with the front document, which have not been completely stoppedby the action of the above portion of air, are brought into contact withthe second vacuum Chamber and retained by the latter.

The present invention also relates to a document feeding deviceincluding a magazine for documents, a feed belt passing adjacent to themagazine along one side of a feed path for the documents and having atleast one opening therein, a first 'vacuum cham'ber positioned adjacentto the feed belt along one side of the path and having at least oneopening therein, and means for exhausting air in the first vacuumChamber, wherein the first vacuum Chamber is operable in Cooperationwith the opening in the feed belt to cause one document at a time to bewithdrawn for the magazine and to be moved along the feed path, and asecond vacuum Chamber positioned along the other side of the feed pathand beyond the magazine considered in the direction of travel of thedocuments, the second vacuum Chamber having at least one opening thereinand being coupled to other exhausting means.

According to the broader aspects of the invention, there is provided adocument feeding device which includes a perforated conveyor belt movedbetween the front document of a stack arranged in a magazine and avacuum Chamber. By the combined action of the vacuum and the travellingconveyor belt the documents are successively separated from the stack.In order to prevent twoor more documents from being simultaneouslyseparated from the stack pressurizcd air is blown through Channels whichare oblique with respect to the plane of the documents in such a mannerthat at least a portion of this air reaches the leading edges of thedocuments in the stack. After having left the magazine the documentsseparated from the stack are moreover subjected to the combined effectof air pressure and suction exerted at the one and other oppositelylocated sides of the conveyor belt, the air pressure and suction beingperpendicular to the plane of the documents and being directed away fromthe vacuum chamber.

BRIEF DESCRIPTION OF THE DRAWINGS The above mentioned and other objectsand features of the invention will become more apparent and theinvention itself will be best understood by referring to the followingdescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a top view of a document feeding device according to thepresent invention, however with two guide plates and a photocellarrangement removed for clarity;

FIG. 2 is a side view along line II-II of FIG. 1 and considered in thedirection of the arrows, including the guide plates and photocellarrangement;

FIG. 3 is a side view along line III- III of FIG. l and considered inthe direction of the arrows, and also including the guide plates andphotocell arrangement; and

FIG. 4 is a side view from left to right of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT The document feeding deviceshown is mounted on a mounting plate 1. It includes a valve the housing2 of which is secured to mounting plate 1 by means of screws such as 3.This valve is for instance of the type disclosed in the Dutch patentapplication No. 6811256 filed on Aug. 8, 1968 and entitled Valve. It isable to establish a communication between vacuum chamber '4 and eitherthe ambient atmosphere or conduit 5 which is connected to exhaustingmeans (not shown) adapted to create an underpressure substantially equalto 0.5 kg./cm.2. Chamber 4 opens in the rear wall 6 of a cavity 7 ofhousing 2 which further has a lateral cut-out portion 8 separated fromcavity 7 by wall 9. Three rollers 10, 11, 112 are mounted in a freelyrotatable manner in the cavity 7 on the respective axles 13', 14,*15which are fixed between the walls 16 and 17 of housing 2, delimitingthis cavity 7. A further roller 18 is mounted in a freely rotatablemanner on axle 19 secured between the same walls 16 and 17 delimitingcut-out portion 8. Rollers '10 to 12 and 18 slightly project beyondwalls 9, 16 and 17 which are all located in a same plane. Wall 9 has aplurality of openings such as 20 which communicate with a pressureChamber 21 which is itself connected to a source of pressurized air (notshown) via conduit 22 which passes through mounting plate 1. Thepressure of this air is substantially equal to 1.14 kg./cm.2.

A guide plate 23 (FIG. 2) is secured to the lower part (FIG. 2) of wall17 of housing 2 in such a manner that it protrudes beyond the plane ofthe above rollers 101 to 12 and 18. Guide plate 24 is fixed to the upperpart (FIG. 2) of wall 16 in such a manner that it is located in the sameplane as guide plate 23. These guide plates 23, 24 are not shown in FIG.1 for clarity. A pressure chamber 25 is fiXed to the upper portion ofguide plate 24 and protrudes beyond the plane of this plate. Pressurechamber 25 has a plurality of channels such as 26 and is connected tothe above mentioned source of pressurized air via conduit 27.

A small block 29 (FIG. 2) housing a lamp 28 schematically represented bya small circle is secured to guide plate 24 in such a manner that lamp28 is located behind cut-out portion 30 of this guide plate.

A perforated belt 31 makes contact with the above rollers 10, 11, 12 and18 and is arranged around rollers 32, 33 and 34 which are able to drivebelt 31 in the direction indicated in FIGS. 1 and 2 by the arrows.Roller 32 is a drive roller and is secured to shaft 35 which isrotatably mounted on mounting plate l by means of a bearing mounted inhousing 36 and which forms part of a motor (not shown). Rollers 33 and34 are mounted in a freely rotatable manner on the respective axles 37and 38 which are fixed on mounting plate 1.

Piece 39 (FIG. 3) is fixed on mounting plate 1 and carries a small block40 which is fixed by means of screws such as 41. Block 40 houses aphotocell 42 which is schematically represented by a small circle andwhich faces lamp 28. This photocell is connected to an electric controlcircuit (not shown). Portion 4-3 of the wall 44, of piece 39, facingbelt 31 has a cavity 45 which is laterally closed by plate 46 which isfixed to piece 39 by means of screws such as 47, 481 (FIG. 1). Acylindrical roller 49 is mounted in this cavity 45 and is continuouslyurged into contact with roller 18 (not shown) by spring means located inthe cavity 45.

Wall portion 43 further has nine small cavities such as 50, which arelocated in front of wall 9 having opening 20, and which extend in adirection parallel to the direction of displacement of the documents.Each of these cavities 50 has an opening such as 51 which issubstantially located in the middle of the cavity and which communicateswith a common vacuum chamber 52 through a channel such as 53 which isperpendicular to wall 43. This vacuum chamber 52 is connected to aconduit 54 which passes through mounting plate 1 and which is itselfcoupled to the above mentioned exhausting means.

Wall portion 43 also has two cavities 55, 56 located on either side ofthe cavities 50 and each having an opening such as 57, 58 located nearone end of the cavity. These cavities 55, 56 also extend in a directionparallel to the direction of displacement of the documents. Openings 57both communicate with pressure chamber 59 via a channel such as 60,while openings 58 both communicate with pressure chamber 61 via achannel such as 6'2. These pressure chambers 59 and 61 in turn bothcommunicate with a common chamber 63 which is itself connected to aconduit 64. This conduit 64 is coupled to another source of pressurizedair the pressure of which is substantially equal to 1.7 kg./cm.2. Thechannels such as and 62 are oblique with respect to wall 43 as clearlyshown in FIG. 1.

It should be noted that the one end of the cavities '50, 55, 56 nearestto the magazine is located on a line perpendicular to the direction ofdisplacement of the documents.

At both sides of portion 43, wall 44 is chamfered as indicated by 65 and66. Mounting plate 1, piece 39 and the assembly constituted by guideplates 23 and 24 and belt 31 delimit a magazine 67 for a stack ofdocuments such as front document 68. This stack is continuously urgedtowards guide plates 23 and 24 by, not shown, but classical means suchas a spring urged weight.

Operation Normally the above mentioned drive motor, exhausting means,and sources of pressurized air are operated while the valve is in afirst or rest condition. Consequently belt 31 is driven in the directionindicated by the arrow around rollers 32, 33 and 34 and over rollers 12,11, 10. An underpressure of approximately 0.5 kg./cm.2 is created invacuum chamber 52 via conduit 54 so that a suction is exerted in theopenings 51 of the cavities 50; a pressure of approximately 1.14kg./cm.2 created in pressure chamber 21 via conduit 22 so that jets ofpressurized air issue from the openings 20; a pressure of approximately1.14 kg./cm.2 is created in pressure chamber 25 so that jets ofpressurized air issue from the openings 26; a pressure of approximately1.7 kg/cm.2 is realized in pressure chambers 63, 59, 61 via conduit 64so that jets of pressurized air issue from the openings 57, 58 in therespective cavities 55, '56; finally, in chamber 4 atmospheric pressureis realized since the valve is in its one condition. The suction exertedin openings 51 and the jets of air issuing from the openings 21 have noeffect. The jets or air issuing from the openings 26 are directedbetween the front documents of the stack and are substantially parallelto the planes thereof and substantially perpendicular to the directionof advancement of belt 31. These jets of air prevent the front documentsof the Stack from sticking together.

The jets of air issuing from the openings 57, 58 are directed againstthe non perforated upper and lower portions of belt 31 so'that a portionof this air is deflected towards the magazine 66 in a direction oppositeto the direction of advancement of perforated belt 31. This portion ofair prevents the leading edges of the front documents from sticking toone another.

When the front document 68 of the stack of documents located in magazine67 must be separated from this stack, the above valve is brought in itsother position by the above-mentioned electric control circuit in orderto establish a communication between vacuum chamber 4 and the aboveexhausting means via conduit 5. Due to this the portion of the frontdocument 68 located in front of cavity 7 is sucked against belt 31 sothat this document is slightly deformed and conveyed through the gapbetween belt 31 and piece 39. Hereby the portions of the document whichare not sucked against belt 31 are prevented from abutting against piece39 since the latter piece is chamfered at both sides 65, 66 of wallportion 43. The advancement of the document 68 thus separated from thestack is not hindered either by the air jets issuing from the openings20, 57, 58 nor by the suction exerted in the openings 51 since thesurface on which a suction is exerted by chamber 4 is larger than thatof the cavities 50. The only elfect of air jets issuing from openings 20and of the suction exerted in openings '51 is that a portion of frontdocument 68 is deflected against wall portion 43 of wall 44 of piece 39.

substantially at the moment the leading edge of this document 68 isgripped between belt 31 and roller 49, it interrupts the light beambetween lamp 28 and photocell 42 due to which the valve is brought backinto its first condition wherein it establishes a communication betweenchamber 4 and the atmosphere. From that moment on the trailing portionof the document is no longer subjected to suction and consequently theadvancement of the document between the belt 31 and roller 49 is nothindered by this suction.

The jets of pressurized air issuing from the openings 57, 58 aredirected in the gap between belt 31 and piece 39 and a portion of thisair has a direction substantially opposite to the direction ofdisplacement of this belt 31 in order to prevent other documents thanthe front one 68 from being separated from the stack. If,notwithstanding the action of this pressurized air, one or moredocuments are separated from the stack together with the front document68, they are considerably braked or even stopped by this air since thesedocuments are only moved, for instance, by the suction effect exertedthrough the belt and the front document or by adhesion to this vfrontdocument.

If one or more documents, which have been separated from the Stacktogether with the front document, have not been stopped by theabove-mentioned jets of pressurized air issuing from openings 57, 58,they are advanced into a position wherein they are subjectedsimultaneously to the pressure of the jets of air issuing from openings21 and to the suction exerted in the openings 51. Consequently theportion of the document nearest to the wall portion 43 of piece 39 ispushed into contact with this wall where it is subjected to the suctionexerted in the openings 51. Due to this it is stopped. The otherdocuments separated together with the front document will be stopped bythe same pressure and suction effect and by the jets of pressurized airissuing from the openings 57, 58.

It should be noted that the volume of air delivered per time unitthrough the openings 21 is larger than that sucked through the openings'51 in order to have an excess of air preventing the documents fromsticking together. It should also be remarked that the cavities 50' havebeen provided in order to have large suction surfaces although theopenings 51 are small, whereas the cavities 55, 56 have been provided inorder that the air issuing from the openings 57, 58 should be guided tosome extent. These cavities have moreover been provided in order thatthe air issuing from the openings 57, 58, should not enter the cavities50.

What is claimed is:

1. In a document feeding apparatus 'which includes a feed belt with aplurality of perforations therein passing along one side of a feed pathfor the documents, a magazine for the documents which is positioned onthe other side of the feed path, and a first vacuum chamber, withassociated first exhausting means, having at least one opening whichcommunicates with the perforations in the feed belt along a portion ofthe one side of the feed path opposite the magazine, so as to cause onedocument at a time to be withdrawn from the magazine and moved along thesaid path, the improvement comprsing:

(a) first means (57-64) for supplying a stream of air and directing atleast a portion thereof between the feed belt (31) and the magazine (67)in a manner such that said portion is directed substantially opposite tothe directon of displacement of the feed belt so as to cause thedocuments to be restrained in the magazine excepting those withdrawn one-at a time therefrom, said first means for supplying and directing thestream of air including a first pressure cham- 'ber (59, 61) andassociated first source of pressurized air positioned along said otherside of the feed path and having at least one opening (57, 58), and achamber (60, 62) communicating with said opening and the feed path suchthat the stream of air issuing therefrom is oblique with respect to thedirection of document displacement;

(b) a second vacuum chamber (52) and associated second exhausting meanspositioned along said other side of the feed path and having at leastone opening (51) which communicates with the feed path between themagazine and said first means; and

(c) a second pressure chamber (21) and associated second source ofpressurized air positioned along said one side of the feed path, saidsecond pressure chamber having at least one opening (20) therein whichcommunicates with the feed path substantially opposite the opening (51)of said second vacuum chamber (52), wherein said oppositely arrangedopenings (51, 20) cooperating to insure the transport of only onedocument at a time along the feed path.

2. The document feeding apparatus according to claim 1 wherein saidopenings in said first pressure chamber and in said second vacuumchamber are aligned in a plane which constitutes a portion of said otherside of the feed path.

3. The document feeding apparatus according to claim 2 wherein saidfirst pressure chamber has at least two openings (57, 58) which arelocated at the one and other sides of said opening in said second vacuumchamber.

4. The document feeding apparatus according to claim 1 further includinga third pressure chamber (25) positioned above the magazine, said thirdpressure chamber having at least one opening (26) therein and beingcoupled to a third source of pressurized air, said opening being suchthat the stream of air issuing therefrom is substantially parallel tothe plane of the documents and perpendicular to the direction ofdocument displacement.

5. The document feeding apparatus according to claim 3 wherein eachopening (57, 58) of said first pressure chamber is made in an individualfirst cavity (55, 56) of a wall of said first pressure chamber.

6. The document feeding apparatus according to claim 5 wherein each saidopening (51) of said second vacuum chamber is made in an individualsecond cavity (50) of a wall of said second vacuum chamber.

7. The document feeding apparatus according to claim 6 Wherein each ofsaid first and second cavities extends along said other side of the feedpath parallel to the direction of document displacernent.

8. The document feeding apparatus according to claim 7 wherein the oneends of said cavities nearest to the magazine are located substantallyon a line perpendicular to the direction of document displacement.

9. The document feeding apparatus according to claim 8 wherein theopening in each first cavity is located substantially near the other endthereof, while the opening in each second cavity is substantiallycentrally located between the one and other ends thereof.

10. The document feeding apparatus according to claim 1 Wherein thevolume of air deli'vered per time unit by said first source (20, 22) ofpressurized air is larger than the volume of air exhausted per time unitby said second exhausting means (52, 54).

11. The document feeding apparatus according to claim UNITED sTATEsPATENTS 3,131,'9`29 5/1964 Rehrn 271-26 3,260,520` 7/1966 Sugden 271--343,312,464 4/1967 Rehm 271-26 4/ 1970` Burk'hardt 271-26 OTHER REFERENCESAnderson et aL-IBM Technical Disclosure Bulletin,

5 vol. 6, No. 2, 1963, pages 32 and 33.

JOSEPH WEGBREIT, Primary Examiner U.S. Cl. X.R. 271 34

